Let's solve both questions step by step:

Question 1 (Sequence with Multiplying and Adding):

Given rule: Start at 3, multiply by 2, and then add 4 each time.

1. Start at 3.
2. Multiply by 2: $3 \times 2 = 6$.
3. Add 4: $6 + 4 = 10$.
4. Multiply by 2: $10 \times 2 = 20$.
5. Add 4: $20 + 4 = 24$.

Thus, the next few terms in the sequence are: 6, 10, 20, 24.

Question 2 (Sequence Subtracting Each Time):

Given rule: Subtract 3 each time, and the 10th term is 24.

1. The 10th term is 24.
2. To find the 12th term, we subtract 3 twice:
   • $24 - 3 = 21$ (11th term).
   • $21 - 3 = 18$ (12th term).

Thus, the 12th term is 18.

Do you need further clarification on any of these steps? Here are some related questions for you to explore:

1. How would you find the 5th term in a similar multiplying and adding sequence?
2. Can you extend the rule of subtracting 3 to calculate earlier terms in the sequence (e.g., the 9th or 8th term)?
3. What happens if you change the rule in the multiplying and adding sequence (e.g., add a different number)?
4. How would you handle a sequence where you multiply by a number and subtract a different number?
5. Can you calculate the 15th term in a sequence that subtracts 2 each time starting from 30?

Tip: When working with sequences, always clearly identify the rule so you can consistently apply it to find any term.